Oct. 21, 2011 -- Frequent hand washing will keep those nasty bugs at bay, right? Not if you're using a public bathroom. Paper dispensers, hand dryers, door handles -- all the things you touch after scrubbing -- are contaminated with all sorts of menacing microbes, sometimes too many to count.

"We documented extensive bacterial contamination of high-touch environmental sites in 22 public restrooms and aircraft," says researcher Lennox Archibald, MD, PhD, of the College of Medicine, University of Florida, in Gainesville.

Translation: Bathrooms in restaurants, resorts, hospitals, and even libraries are crawling with bugs that can cause everything from diarrhea to wound infections.

"You can go paranoid thinking about it," Archibald tells WebMD.

Variety of Bacteria in Public Restrooms

There's been virtually no research into how many bacteria, and how many different types of bacteria, lie in wait in public restrooms, he says.

So from December 2010 through February 2011, his team descended on restrooms inside four commercial aircraft and 18 public places, including a mall, a hospital, offices, a lecture hall, a conference center, department stores, restaurants, an airport, and a resort.

The researchers hit the microorganism jackpot. They recovered staph, which can cause everything from boils to antibiotic-resistant infections. They found E. coli. They cultured Enterococcus, a fecal bug that can cause urinary tract infections and wound infections. And more.

Cultures of high-touch sites in three hospital restrooms yielded seven bugs that are responsible for two-thirds of hospital-associated infections.

The findings were presented at the annual meeting of the Infectious Diseases Society of America (IDSA) in Boston.

Keeping Away From Bacteria

For Archibald, one solution is to hold it in. "I only use bathrooms on very long-distance flights," he says.

For those times when you have to go, carry paper towels or tissues to protect your hands after washing, he says.

William Schaffner, MD, chair of IDSA's immunization work group and head of preventive medicine at Vanderbilt University Medical Center in Nashville, has a more bug-friendly viewpoint.

Some bacteria boost our immune system, he tells WebMD.

"We don't live in a sterile world," Schaffner says. "You don't want to obsess. On the other hand, you want to be hygienic," he says.

His tip: Carry a little vial of hand sanitizer where ever you go.

These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.